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171.
Zhong-zhi Bai 《计算数学(英文版)》1998,(6)
1.IntroductionTheclassicaliterativemethods,suchastheJacobimethod,theGauss-SeidelmethodandtheSORmethod,aswellastheirsymmetrizedvariants,playanimportantroleforsolvingthelargesparsesystemoflinearequationsInaccordancewiththebasicextrapolationprincipleofthelineariterativemethod,Hadjidimos[1]furtherproposedaclassofacceleratedoverrelaxation(AOR)methodforsolyingthelinearsystem(1.1)in1978.Thismethodincludestwoarbitraryparameters,andtheirsuitablechoicesnotonlycannaturallyrecovertheJacobi,theGauss-S… 相似文献
172.
This article explores the use of geometric algebra in linear and multilinear algebra, and in affine, projective and conformal geometries. Our principal objective is to show how the rich algebraic tools of geometric algebra are fully compatible with and augment the more traditional tools of matrix algebra. The novel concept of an h-twistor makes possible a simple new proof of the striking relationship between conformal transformations in a pseudo-Euclidean space to isometries in a pseudo-Euclidean space of two higher dimensions. The utility of the h-twistor concept, which is a generalization of the idea of a Penrose twistor to a pseudo-Euclidean space of arbitrary signature, is amply demonstrated in a new treatment of the Schwarzian derivative. 相似文献
173.
In this paper we face the problem of stowing a containership, referred to as the Master Bay Plan Problem (MBPP); this problem
is difficult to solve due to its combinatorial nature and the constraints related to both the ship and the containers. We
present a decomposition approach that allows us to assign a priori the bays of a containership to the set of containers to
be loaded according to their final destination, such that different portions of the ship are independently considered for
the stowage. Then, we find the optimal solution of each subset of bays by using a 0/1 Linear Programming model. Finally, we
check the global ship stability of the overall stowage plan and look for its feasibility by using an exchange algorithm which
is based on local search techniques. The validation of the proposed approach is performed with some real life test cases.
This work has been developed within the research area: “The harbour as a logistic node” of the Italian Centre of Excellence
on Integrated Logistics (CIELI) of the University of Genoa, Italy 相似文献
174.
N. B. Brusnikina A. V. Lotov 《Computational Mathematics and Mathematical Physics》2007,47(11):1779-1787
A method is proposed for approximating the reachable set of a dynamic system with a state space dimension no higher than six-eight considered on a finite time interval. The system is governed by linear differential equations with piecewise constant coefficients and impulse actions specified at prescribed times. The method is based on guaranteed-accuracy polyhedral approximations of reachable sets at researcher-specified times. Every approximation is constructed using the preceding one. A procedure is described for choosing parameters of the method that ensure the required accuracy with close-to-minimal time costs. 相似文献
175.
176.
朱方生 《武汉大学学报(理学版)》1995,(3)
构造了线性二次型最优控制的并行算法,介绍了这个并行算法在武汉大学“WUDP91”并行分布式处理系统上试算的数值应用软件的框图.本软件适用于既定动态系统的平衡问题.对于经济系统,可通过政策控制变量来调节和改善其状态和响应.对于自治系统可找出最优控制使得消耗函数达到最小值.通过对一系列例子进行试算,结果证实,所构造的并行算法和相应的数值软件是有效的,其加速比约为7. 相似文献
177.
Lubomír Kubáček 《Mathematica Slovaca》2007,57(1):59-82
In some situations estimates of unknown parameters must be corrected by additional measurements. It is in principle no problem
to calculate the corrected estimates, however, it is of more interest to find formulae for correction itself. The formulae
enable us to design an additional experiment and to judge its usefulness.
The aim of the paper is to find such formulae for several situations.
Supported by the grant of the Council of Czech Government MSM 6 198 959 214. 相似文献
178.
179.
Carlo Carlini Valentina De Luise Anna Maria Raspolli Galletti Glauco Sbrana 《Journal of polymer science. Part A, Polymer chemistry》2006,44(1):200-206
Novel catalytic systems, prepared in situ by the oxidative addition of 8‐hydroxyquinoline ligands to bis(1,5‐cyclooctadiene)nickel(0) and activated by methylaluminoxane, were studied in ethylene polymerization. When 8‐hydroxyquinoline was employed, only oligomeric products were obtained. On the contrary, 5,7‐dinitro‐8‐hydroxyquinoline gave linear polyethylene (PE), but with a modest activity. For the catalyst based on 5‐nitro‐8‐hydroxyquinoline, the productivity was largely dependent on the content of free trimethylaluminum (TMA) present in the commercial aluminoxane. The progressive optimization of the TMA/oligomeric methylaluminoxane ratio increased the productivity, which reached 700 kg of PE/(mol of Ni × h), by an order of magnitude. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 200–206, 2006 相似文献
180.
将Phelps引理, Ekeland变分原理, Pareto有效性定理推广到拓扑线性空间,同时证明了这三个定理与郑喜印证明的拓扑线性空间中的Drop定理彼此等价. 相似文献